How much volume should be added when installing a device in a box?

When installing a device in a box, the National Electrical Code (NEC) requires that an additional volume be accounted for to ensure that there is sufficient space for conductors and to maintain safety and functionality. According to NEC guidelines, when you install a device such as a switch or receptacle, you should add 2.0 cubic inches of volume to the box size. This volume is essential for accommodating the wiring connections securely without overcrowding, which could lead to heat buildup or insulation damage.

Adding this additional volume maintains compliance with the NEC, allowing for safe and accessible electrical installations. It’s crucial to adhere to this requirement to ensure that all conductors can fit within the space provided, thus preventing possible violations of the code that may lead to safety hazards.